[llvm] [CodeGen][NPM] Port MachineBlockPlacement to NPM (PR #129828)

[Akshat Oke via llvm-commits]

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@@ -608,18 +613,48 @@ class MachineBlockPlacement : public MachineFunctionPass {
   /// Create a single CFG chain from the current block order.
   void createCFGChainExtTsp();
 
+public:
+  MachineBlockPlacement(const MachineBranchProbabilityInfo *MBPI,
+                        MachineLoopInfo *MLI, ProfileSummaryInfo *PSI,
+                        std::unique_ptr<MBFIWrapper> MBFI,
+                        MachinePostDominatorTree *MPDT, bool AllowTailMerge)
+      : MBPI(MBPI), MBFI(std::move(MBFI)), MLI(MLI), MPDT(MPDT), PSI(PSI),
+        AllowTailMerge(AllowTailMerge) {};
+
+  bool run(MachineFunction &F);
+
+  static bool allowTailDupPlacement(MachineFunction &MF) {
+    return TailDupPlacement && !MF.getTarget().requiresStructuredCFG();
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optimisan wrote:

Same check is done for EnableTailMerge also.

https://github.com/llvm/llvm-project/pull/129828